Several industries, including motor vehicle, transportation and insurance, desire to have a device in the safety belt system of a motor vehicle which will indicate whether or not the safety belt was worn during an impact collision. Also, if the device was worn, when the collision occurred. In the past, the loading could only be determined when the belt was abraded, chafed or if the metal supports were bent or broken. However, many vehicle collisions are not severe enough as to bend or break the metal supports since they are made of very durable material. Thus, by a visual examination of a built-in safety belt assembly, it is not always possible to determine if the safety belt assembly was subject to a collision or if excessive forces had been exerted on the assembly.
In other industries it may be desirable to monitor shipping and handling of goods such that should damage to the goods occur the time of undue damage could be ascertained.
In order to overcome the inability to determine whether or not a safety belt was worn during a collision, it is one of the primary objects of the present invention to provide a safety belt assembly which determines the amount of force exerted on the safety belt assembly.
An additional objective of the present invention is to provide a chemical timer which will indicate elapsed time since the point in time when the excessive force was exerted on the safety belt assembly.
It is still further an objective of the present invention to provide an assembly which is responsive to forces exerted on items during shipping and the like which will indicate excessive force caused by mishandling or accidents during shipment of a product and the elapsed time, since such a force occurred.
To achieve the foregoing objectives, the assembly according to the present invention includes a first and second plate associated with one another; a flat elongated biasing member associated with the plates for resiliently restraining relative movement and movably retaining the plates with respect to one another; a mechanism responsive to relative movement of the plates for enabling a determination of an amount of force or responsive to relative for enabling a determination of when a predetermined limit of force has been exceeded or exerted on the assembly; and a mechanism for securing the assembly to a conventional safety belt and buckle or to a shipping container or goods to be monitored.
Also disclosed is a mechanism substantially similar to the above described assembly having a mechanism responsive to movement of the plates for indicating a point in time when a force was exerted on the assembly. Further, an assembly including both a mechanism for enabling a determination of an amount of force exerted on the assembly combined with a reactive chemical system for indicating elapsed time since a predetermined force was exerted on the assembly is disclosed.
From the following description and claims, taken in conjunction with the accompanying drawings, other objects and advantages of the present invention will become apparent to one skilled in the art.